Tl*the contact owns a 2007 lexus ls460. the contact stated that the emergency brake control button only engaged while depressed; and he had to hold the button the entire time the vehicle was in motion. when the vehicle was stationary, the button would remain engaged. the contact believed that the control button should release if pressed twice. the contact notified the manufacturer who stated that the vehicle was designed in that manner. the vin was unavailable. the current and failure mileages were 64,721.